RestAPI: can't create new groups in a course

diff --git a/src/main/java/org/olat/restapi/repository/course/CourseGroupWebService.java b/src/main/java/org/olat/restapi/repository/course/CourseGroupWebService.java
index 58623e9..4dc1509 100644
--- a/src/main/java/org/olat/restapi/repository/course/CourseGroupWebService.java
+++ b/src/main/java/org/olat/restapi/repository/course/CourseGroupWebService.java
@@ -51,6 +51,8 @@
 import org.olat.core.util.vfs.QuotaManager;
 import org.olat.core.util.vfs.VFSContainer;
 import org.olat.core.util.vfs.VFSManager;
+import org.olat.course.CourseFactory;
+import org.olat.course.ICourse;
 import org.olat.group.BusinessGroup;
 import org.olat.group.BusinessGroupService;
 import org.olat.group.model.SearchBusinessGroupParams;
@@ -212,7 +214,8 @@
 	@Consumes({MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON})
 	@Produces({MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON})
 	public Response putNewGroup(GroupVO group, @Context HttpServletRequest request) {
-		if(!RestSecurityHelper.isGroupManager(request)) {
+		ICourse icourse = CourseFactory.loadCourse(course.getResourceableId());
+		if(!RestSecurityHelper.isGroupManager(request) && !RestSecurityHelper.isOwnerGrpManager(icourse, request)) {
 			return Response.serverError().status(Status.UNAUTHORIZED).build();
 		} else if(course == null) {
 			return Response.serverError().status(Status.NOT_FOUND).build();
diff --git a/src/main/java/org/olat/restapi/security/RestSecurityHelper.java b/src/main/java/org/olat/restapi/security/RestSecurityHelper.java
index 8804b11..d67190c 100644
--- a/src/main/java/org/olat/restapi/security/RestSecurityHelper.java
+++ b/src/main/java/org/olat/restapi/security/RestSecurityHelper.java
@@ -79,6 +79,19 @@
 		}
 	}
 	
+	public static boolean isOwnerGrpManager(ICourse course, HttpServletRequest request) {
+		try {
+			Roles roles = getRoles(request);
+			if(roles.isAdministrator()) return true;
+			CourseGroupManager cgm = course.getCourseEnvironment().getCourseGroupManager();
+			UserRequest ureq = getUserRequest(request);
+			Identity identity = ureq.getIdentity();
+			return cgm.isIdentityCourseAdministrator(identity) || cgm.hasRight(identity, CourseRights.RIGHT_GROUPMANAGEMENT);
+		} catch (Exception e) {
+			return false;
+		}
+	}
+
 	public static boolean isAuthorGrpManager(ICourse course, HttpServletRequest request) {
 		try {
 			Roles roles = getRoles(request);